Art of incorporating drying metals in paints, varnishes, linoleums, inks, etc.



Patented June 23,1942

ART OF INCORPORATING DRYING METALS IN PAINTS, VARNISHES, LINOLEUMS; INKS,

ETC.

Arthur Minich, Elizabeth, N. 3., assignor to Nuodex Products (70., Inc., Elizabeth, N. J., a corporation of New York No Drawing. Application March 26, 1940, Serial No. 326,006

4 Claims. (Cl. 106 -3'10) This invention relates to driers for paints, varnishes, enamels, linoleums, printing inks, etc., and the invention is directed, more particularly, to the incorporation of drying metalsinto such -end products of commerce.

Drying metals, as contemplated by this invention, include, among others, the following: .lead, cobalt, iron, manganese, nickel, zinc, calcium, barium, cerium.

.It has been heretofore common to incorporate salts of these drying metals in paints, varnishes, linoleums, etc., in certain well defined ways. For example, these salts have been introduced in powdered form, by grinding them with vehicles at room temperature. They have also been associated with vehicles by commingling them in liquid form. ,Ithas also-been the practice in some instances to fuse metal compounds, including the desired drying metal or metals, with the vehicles into which they are to be incorporated,such, for example, as by cookinglitharge with rosin or cobalt acetate with a linoleum vehicle.-

.In the preparation of cooked driers, it has been customary to employ a vehicle which may-consist of oils or resins, or both, in conjunction with somevolatile solvent which is added after the reaction is completed.- The metal compounds such as naphthenates or linoleates,- they are usually tough and dense masses which are diflicult to manipulate. The resinates. have poori -solubility and require long periods of the application of heat in order to dissolve them in the vehicle. All of these difficulties which have attended conventional prior practice are satisfactorily overcome by the present invention in a simple, ecopreviouslyemployed for this purpose have been i of a wide variety. .For example, cooked lead driers have been commonly produced from litharge, lead acetate. and also from the solid naphthenate, resinate or linoleate of lead. In the case of manganese, the raw materialhas commonly been manganese dioxide, manganese borate, manganese acetate, as well as the solid resinate, naphthenate or linoleate of manganese. In,the case of these solid compositions, they have been derived by fusion or by double decomposition. Cobalt has been produced from cobalt carbonate, cobalt acetate, or the solid linoleate, resinateor naphthenate of cobalt.

The-employment of all of these metal compounds in the process ofcookingpresents certain well recognized dimculties. .For example, when using manganese dioxide, it is very diflicult to obtain complete reaction. With litharge, or lead acetate, the lead tends to-settle to the bottom thereby interfering with the heating, as well as making it still more diflicult to bring it into solu tion in the total mass. tates, such as ,cobalt acetate, it is practically im- In the case of the acepossible to completely drive off the acetic-acid and any remnants of this acid which remain will seriously interfere with th stability and drying efliciency of the drier. In the use of solid driers.

nomical and efllcient way as will be hereinafter more fully described.

.The present invention deals primarily with the incorporation of appropriate, substantially waterinsoluble, organic hydroxy salts of the drying metals into the compositions into which theyare to be introduced,-at such elevated temperatures as to bring about chemical reaction between the hydroxy metal salt and th vehicle, whereby the hydroxy metal salt is solubilized and thus enters solution in such vehicle. Under prior practice, where elevated temperatures were used with metal compounds, such as cobalt acetate or litharge, or manganese borate, such hydroxy metal salts have not heretofore been used. 3

By solubilized, I mean that the drying metal salt is rendered soluble-in the vehicle into which it is to be incorporated whereby it is enabled to go into solution therewith as specified.

In practically carrying out the present invention, the, hydroxy metal salt or salts employed are first prepared. The following procedures have been found to give highly satisfactory results.

COMPOSITION A.- Hydro.1:y cobalt salt (23% cobalt metal content) ingredients Pounds Caustic soda 10o Naphthenic acid (acid N0. 240) 225 Water 2800 Cobalt sulphate crystals 331 Water 400 PROCEDURE Total yield-278 lbs.

manganese metal content) Ingredients: Pounds Caustic soda 101.5 Naphthenic acid (acid number; 240) 212 Water Manganese sulphate (30% manganese) g 240 Water 600 PROCIDURI Same as with Composition. A: i. e., prepare aqueous-caustic soda-naphthenic acid-solution and add thereto aqueous manganese sulphate solution, and thereafter decant, filter and dry.

The resulting product is a dry, loose, relatively porous, hydroxy manganese salt which may be broken down as hereinbefore stated.

Total yield-280 lbs.

Courosmon C.-Hudro:cy iron salt (28% iron Courosrrron B.Hudro:cu manganese salt (24% metal content) Ingredients: Pounds Caustic soda 93 Napththenic acid (acid number 234) 185 Water 2500 Ferric chloride crystals .Q; 300 Water 400 The procedure and-sequence of operation is as described in connection with Composition A.

Total yield-220 lbsdoi' hydroxy iron salt.

Comosr rron D.-Hydroa:y lead salt (64% lead metal content) Ingredients: Pounds Caustic soda 155' Naphthenic acid 216 Water 1500 Lead acetate 720 Water 900 The procedure and sequence of operation is as described under Composition A.

Total yield-630 lbs. of hydroxy lead salt.

It is also possible to vary the formula and metal content of the hydroxy metal salts employed. E. g., a cobalt of from 18% to 28% has been prepared by following the procedure of Composition A, but with variation in the relative percentages Courosrrron E.-Hudro.'au lead salt (62% metal con tent) Ingredients: 1 Pounds Hydrogenated rosin 40 Naphthenic acid (acid number 265).-- 200 Caustic soda 155 Water 1300 Lead acetate. 720 Water 900 Pnoermmu: It is convenient to heat the hydrogenated rosin to 250 F. and then mix it with the n'aphthenic acid. Process is then as described with reference to Composition A. Total yield-670 pounds of Courosrrron F.Hydro:cy.manoanese salt (30% metal content) Ingredients: Pounds 2-Ethylhexoic acid 95 Oleic acid 83 Caustic soda 101% Water 2000 Manganese sulphate (30% manganese) 240 Water g 600 Sequence and process same as hereinbefore described.

Total yield-240 lbs. of hydroxy manganese salt.

Courosrrron G.--Hydro:ru cobalt salt (20% metal content) Ingredients: Pounds Castor oil fatty acid 230 Caustic soda -91 Water 2800 Cobalt sulphate crystals 300 Water 300 Process as previously described. Total yield-307 lbs. of hydroxy cobalt salt.

I have found that compositions of the charac-' ter hereinbefore described, may be utilized for the production of commercial end products, such as cooked driers, paints, varnishes, linoleums, printing inks, and other coating compositions, having vehicles which are organic, water-insoluble and film-forming and which depend upon oxidation for drying.

In order that the present invention may be clearly understood with reference to the cooking of driers into vehicles, I shall compare prior practice with that of the present invention, by first giving a conventional formula and then the a corresponding procedure of invention.

Exam IA.--Lead-man ganese Japan drier (conventional practice) Raw linseed oil gallons 2 East India gurn pounds '72 Litharge ..do 16 Red lead do 15 Black oxide of manganese;. do 22% Solvent ons" Total yieldgals.

This drler requires about 2 hours of cooking in the varnish kettle and a considerable sludge is formed due to the limited solubility of the inorganic metal salts used.

Exams: I.This invention In the formula of Example Ia, I substituted,

for the litharge, red lead and oxide of man-' I ganese, the following:

' Pounds My hydroxy lead salt of 64% metal content-.. 30

My hydroxy manganese salt of 24% metal content 35 and found that the processing time was cut in half; that the yield was increased by 5 gals. to

gals; and that the drier possessed a drying ,hydroxy lead salt.

strength at least equal to the drier of Example Ia. Furthermore, it had a paler color, was free from sludge and its solubility was greater than the end product of Example Ia. I thus not only obtained a better end product drier butaccomplished marked economies in its preparation because the cooking time was cut in-half. 'Moreover, there was a pronounced absence of that frothing which accompanied the procedure of 7 Example Ia, and, consequently, larger batches may be prepared in the same capacity kettle. With the present invention, the reaction is much faster and vigorous agitation (such as is necessary when using litharge or other inorganic salts) is not here required.

EXAMPLE m.conventional practice- Total yield208 gals.

This formula requires about 1% hours processing. The resultant drier will show a considerable amount of suspended material and will be dark in color.

EXAMPLE II.--This invention I By substituting my hydroxy lead and manganese salts for the inorganic lead and manganese compounds by employing:

1 Pounds Hydroxy lead. salt, 64% metal 48 Hydroxy manganese salt, 24% metal the time of processing was reduced by 38%. The total yield of the end product was increased by 8 gals., making a total of 216 gals. The drying performance of this formula was slightly superior to that of Example IIa, although its yield was increased. Its color was definitely better and its stability in vehicles was far superior to that of the formula for which it was substituted.

EXAMPLE IIIA.Conventi0nal practice Rosin pounds 200 Linseed oil gal1ons l5. Lime (calcium hydroxide) pounds 14 Cobalt acetate do Thinner gallons 80 Total yield-110 gals.

Duetothe vry pronounced foaming and frothing of the cobalt acetate, it was necessary to introduce this salt in small portions. Furthermore, it required considerable time and attention to boil oil all acetic acid which was liberated in the course of the reaction. The overall time of reaction with this formula was approximately 3v sw hicles was much better than that of Example me. Its color was also superior to that of the latter formula. In spite of the increased yield obtained, the drying performance was slightly superior to that of Example IIIa. This perhaps might bedue in some degree to the fact that often driers prepared from cobalt acetate retain some acetic acid, which exerts a detrimental effect upon drying.

EXAMPLE IVA.Conventional practice Rosin pounds 400 Linseed oil gallons 30 Linseed oil fatty acids do 5 Litharge pounds 40 Cobalt acetate do 20 Thinner gallons 160 Total yield-230 gals. As in Example Illa, the introduction of cobalt acetate was accompanied by strong foaming. It was necessary to stir vigorously and the entire reaction was rather slow, requiring about 3 hours to complete. The end product carried some suspended matter due to the fact that it is impossible to obtain complete conversion of the inorganic salts employed 'in this formula.

EXAMPLE IV.This invention When in place of 'the cobalt acetate and litharge, 18 lbs. of my hydroxy cobalt salt (23% metal) and 45 lbs. of my hydroxy lead salt (64% metal) were employed, the entire reactionwas carried out in 1 hours. The total yield in creased by 5. gals., making a total of 235 gals. The resultant, drier was perfectly clear and had superior drying performance to the end product of Example Iva..- Its staining was less and its color was far better than that of the cobalt acetate drier. Its solubility and stability in paint and varnish vehicles was very much superior to that of the acetate drier. Furthermore, due to the complete absence of acetic acid in this formula, there was no danger of discoloring sensitive lake colors in enamels, etc. in which it might be incorporated. On the contrary, acetate driers often, due to the retention of acetic acid, exert a highly objectionablereaction' and discoloration on certain sensitive pigments which are employed in the manufacture of paints and enamels.

EXAMPLE VA.C'onventional practice Pounds Improved linseed il 620 Rosin 400 Fumed litharge 80 Manganese dioxide 15 Cobalt hydroxide; 5 Mineral spirits 1800 Total yield2600 lbs. This formula requires 3% hours for processing.

The resultant, drier carried some suspended matter due to incomplete reaction of the inorganic metal compounds used. The color was rather dark and the staining power objectiona'bly high.

EXAMPLE. .V.-This invention When a substitution with my hydroxy metal Hydroxy-cobalt salt (23% metal) 12 accomplished in 1 hours. The total yield increased by not less than 200 lbs. due to the presence of the hydroxy salts themselves, and also due to the much lower cooking loss because of faster reaction and lower temperatures. In spite of the extra yield, the resultant drier showed a slightly superior dryingperformance over the end product of Example Va. Its color and staining were much more satisfactory than of the drier which it replaced. Furthermore, its solubility and stability in vehicles in which it was incorporated was much better thanthat of Example Va.

It is also possible to utilize the hydroxy metal salts hereinbefore described in the preparation of solid driers, such as, for example, resinate.

driers, with the absence of any oils or solvents. For example, cobalt resinate or cobalt linoleate is often prepared by fusion of cobalt acetate with rosin or linseed oil fatty acids. For this purpose,

it is possible to substitute the hydroxy cobalt salt (23% metal) forthe acetate.

I have alsofound that it is possible to reactv my hydroxy metal salts with various other waterinsoluble, organic acids at temperatures above the decomposition temperatures of such ts.

Examples of such acids are oleic acid, ricinol ic acid and capric acid. While these acids, as such, are not necessarily film-forming, their metal salts may be used in film-forming vehicles.

EXAMPLE VIA.-Conventional practice Exsmru; VL-This invention When in place of the cobalt acetate an equal amount of my hydroxy cobalt salt (23% metal) was used (21.4 lbs.), the reaction proceeded very speedily and with very little foaming. The entire process was carried out in less than 1 hour. The resultant product showed superior color, drying performance and stability, to the acetate drier.

It was also found possible to produce similarly the resinates. or linoleates of the hydroxy lead or manganese salts.

' Farmer: VIIn-Gonziention practice 43 lbs. of manganese acetate were introduced into a batch of 207 lbs. of linseed oil fatty acids. Due to the strong foaming which always accompanies the fusion of acetates, and due to the necessity of driving off as much as'possible of the liberated acetic acid, it was required to react for a period of about 2% hours.

ExmrLs ViL-Tlyis invention When in place of the manganese acetate'the equivalent amountof my hydroxy manganese salt was used in the fusion, the entire reaction progressed so rapidly and with so little foaming that it was concluded in less than 1 hour. The

end product possessed better stability and su- 2,287,116 it was found that the entire process could be I also found that it is possible to utilize my hydroxy metal salts by cooking them directly into oils, varnishes, etc. For various reasons, such as gasprooflng. quicker bodying, better drying, higher gloss, etc., drying metal salts, such as litharge, cobalt acetate, lead acetate, as well as the solid naphthenates, resinates or linoleates are sometimes directly introduced into the oil, varnish or other vehicle while being heated- For this purpose my hydroxy compounds work out excellently.

EXAMPLE WRAP-Conventional practice in a 100 gal. batch of heavy bodied quick dry were employed during cooking of the varnish.

' Exsnrm: VIII.-This invention It was found that the use of 0.6 pound of my hydroxy lead salt metal content) and 0.1

pound of my hydroxy manganese salt (30% .metal content) would produce better drying, better color and freedom from sludging.

From the foregoing examples, it will appear that in carrying out the present invention in its preferred form, I first produce an aqueous solution of an alkali salt of an organic acid capable of rendering the substantially water-insoluble hydroxy salt of at least one predetermined drying metal soluble in a film-forming vehicle at a temperature above the reaction point of such hydroxy salt. This solution also contains free hydroxide of such alkali metal. I separately produce an aqueous solution of a water-soluble, inorganic salt of such drying'metal in excess of the amount to molecularly react with the-normal alkali salt of said acid forreacting with the caustic alkali of the first solution. I then commingle these solutions so that they may interact to produce a substantially water-insoluble organic hydroxy salt of the drying metal or metals employed. At the conclusion of the reaction, I isolate the hydroxy metal salt thusproduced, preferably dry the same and in appropriately divided form introduce it into an organic, waterinsoluble, film-forming, oxidizable vehicle and raise the temperature to a point sumcient to react my hydroxy drying metal salt with said vehicle to produce the desired end product.

It will be noted from the foregoing examples that the use of my hydroxy drying metal salts,

as as specified, has many important advantages,

for example:

1; They are very easy to handle (They may be either in powder form or'in the form of nu gets or even coarser particles if desired.)

.2. They react very rapidl and with a'minimum of foaming.

3. They permit the cooking of largerbatches because of quick reaction and the absence of foaming.

4. They introduce no extraneous compounds or .acids into the cooked drierjfwhich might'ulti- 7o extraneous acids such-as acetic acid, which'inight' mately exert a detrimental er ct upon drying performance.

5. They do not introduce into the drier any react and discolor certain paint and enamel pigments.

6. They disperse and dimolve so rapidly in the kettle that strenuous agitation is unnecessary.

perior drying performance to the acetate drier. 7. They do not form a sediment in the kettle during the reaction, such as is usually the case with customary metal salts.

8. Because they disperse and dissolve so quickly in the cooking vehicle they do not reduce to the metal and thus become inactive and worthless such as is often the case when metal compounds, such as litharge, are used.

9. They react at, relatively low temperatures which results in a reduction in cooking losses and fuel economies.

10. The end product driers are non-sludging and, therefore, do not require tanking for a protracted period, which is usually necessary with cooked driers because of the presence of sludge in them.

11. The resultant driers made from them are paler in color than similar driers made from materials such as manganese dioxide.

12. The end products possess improved solu-.

' mensurate with the appended claims.

Having thus fully described the invention,

what I claim as new and desire to secure by Letters Patent is:

1. The process of producing a solution of a hydroxy salt of a drying metal in an oxidizable film-forming material of the class consisting of drying oils and oil vamishes, which comprises producing an aqueous solution containing an alkali metal salt of a water insoluble non-volatile, non-aromatic organic acid capable of rendering the hydroxy salt of a predetermined. drying metal soluble in said film-forming vehicle at a temperature above the reaction point of said hydroxy metal salt and said vehicle and also containing free hydroxide of the alkali metal, separately producing an aqueous solution of a water-soluble inorganic salt of said drying metal in suflicient quantity to react with the alkali salt of said acid and also the free hydroxide of said alkali metal, then mixing the said solutions to form a hydroxy metal salt of the drying metal, isolating the said hydroxy metal salt, adding a minor quantity of drying oils and oil varnishes, which comprises producing an aqueous solution containing an alkali metal salt of naphthenic acid and free hydroxide of the alkali metal, separately producing an aqueous solution of a water soluble inorganic salt of said drying metal in sufiicient quantity to react with the alkali salt of the naphthenic acid. and also the free hydroxide of said alkali metal,

then mixing the said solutions to form a hydroxy naphthenate salt of the drying metal, isolating the said hydroxy naphthenate salt, adding a minor quantity of said salt to such an oil or varnish material, and thereafter heating the mixture to a.sufliciently high temperature to efiect complete chemical reaction and solution between the said hydroxy naphthenate salt and said oil or varnish material.

3. The process of producing a solution of a hydroxy salt of a drying metal in an oxidizable film-forming material of the class consisting of drying oils and oil varnishes, which comprises producing a hydroxy metal salt of a drying metal and a water insoluble, non-volatile, non-aromatic organic acid capable of rendering such hydroxy salt of such drying metal soluble in an oxidizable film-forming material of said class, then adding a minor quantity of said hydroxy drying metal salt to such an oil or varnish material, and thereafter heating the mixture to a sufliciently high temperature to efiect complete chemical reaction and solution between said hydroxy salt and said oil or varnish material.

4. The process of producing a solution of a hydroxy naphthenate salt of a drying metal in an oxidizable film-forming material of the class consisting of drying oils and oil varnishes, which comprises producing a hydroxy naphthenate salt of a drying metaL'then adding a minor quantity of the said hydroxy metal salt to such an oil or varnish material, and thereafter heating the mixture to a sufficiently high temperature to effect complete chemical reaction and solution between the said hydroxy salt and said oil or varnish materials.

' ARTHUR MINICH. 

